Physico-Chemical nanomaterials science

Water evaporation from cellulose based materials with different pore sizes
Brytan A.V., Alekseev O.M.  Andrusenko D.A., Lazarenko M. M.,
Vasylyuk S.V. Zabashta Yu. F.1 
1Department of Molecular Physics, Physics Facult,  Taras Shevchenko National Kyiv University,  64/13 Volodymyrska str., Kyiv, 01601, Ukraine,
E-mail: a_britan@ukr.net
The water evaporation from the porous materials surface is the process that significantly depends on the material spatial structure and the pores geometric parameters distribution. This fact is caused by the mass and heat transfer processes within the volume depend on such type parameters and can differ meaningly for materials with different pores types [1,2].
The work represents data of experimental investigation of water evaporation from different materials surfaces in the air for atmospheric pressure and different values of ambient temperature (50, 60, 70 and 80 C). For pore size influence investigation cellulose-based materials with various pore sizes were chosen: filter paper, fabric, and bandage.
In the experiments sample mass dependences on time were measured at the time during water was evaporating from its surface. By using obtained experimental data water concentration in material (moisture content) time dependences were calculated. A simplified model of the water diffusion process inside the samples was proposed. The activation energies of water molecules diffusion in these materials were determined.

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